Answer:
20 m/s
Explanation:
Step 1
Find the acceleration
We calculate the acceleration of the vehicle travelled
= Speed/Time
Initial speed = 40 m/s
Tims = 5 seconds
Acceleration = 40m/s/ 5s
Acceleration = 8 m/s²
Step 2
Find the distance travelled
Distance travelled = 1/2 × a × t²
= 1/2 × 8 m/s² × 5²
= 100 meters
Step 3
Find the average speed
The average speed = Distance/time
= 100 meters/5 seconds
= 20 meters per second (m/s)
The second
option is the answer
Answer:
Explanation:
|F-->1| = E-->1 x charge on proton
= 300 x 1.6 x 10⁻¹⁹
Magnitude of electric force on proton
|F-->1| = 480 x 10⁻¹⁹ N .
Inside lithium nucleus , there are three protons so charge on it
= 3 x 1.6 x 10⁻¹⁹ = 4.8 x 10⁻¹⁹ C .
Magnitude of electric force on lithium nucleus
|F-->Li| = E-->1 x charge on lithium nucleus
= 300 x 4.8 x 10⁻¹⁹
= 1440 x 10⁻¹⁹ N .
Electron has same charge as that possessed by proton so charge on electron = 1.6 x 10⁻¹⁹ C
Magnitude of force on electron
|F-->1| = E-->1 x charge on electron
= 300 x 1.6 x 10⁻¹⁹
= 480 x 10⁻¹⁹ N .
A critical angle is described as the angle of incidence provided that the angle of refraction is equal to 90 degrees. The value of the critical angle depend on factors such as the materials present on different sides of the boundary. The critical angle of <span>glass-water boundary is 39.3 degrees</span>